As I power on my sony led tv with the help of remote, small red light

@sanjayiddelhi this sounds like your TV goes into a self protection mode. You will have to tell us what exact model this is and what you have checked so far. You do need to try all different inputs and disconnect everything else (soundbar etc.) Just use one input source at a time. If that does not make a difference you do want to unplug your set and remove the back. Then take a close look at your boards. Check for domed, leaky capacitors. Post some images of all of your boards with your question so that we see what you see. Use this guide Adicionar imagens a uma pergunta já existente for that. Right now I would focus on the power board which could be the main culprit by not providing the proper voltages.